Chemical analyses were carried out on 18 of the most popular varieties of fish products in the Polish market (canned, smoked, salted and marinated fish of different species), produced by the largest manufacturers and distributors in the country. The contents of the nutritive substances in the fish products (proteins, amino acids, and fats) were determined. To assess the nutritional quality of proteins in these products, the protein digestibility was determined, which ranged from 77.0% to 98.7%, and the amino acid composition of each of these groups of products was compared with that of a standard protein recommended by the World Health Organization (WHO). In addition, protein digestibility-corrected amino acid scores (PDCAAS) were calculated. Relative to the WHO protein standard, most of the fish products tested scored very high, with values ranging between 0.9 and 1.0. This study confirmed that in terms of both quantity and quality, fish products in the Polish market could serve as a significant source of essential amino acids and that the sulphur-containing essential amino acids and lysine present in fish products could supplement the corresponding deficiency in plant proteins. However, it was also indicated that drastic thermal processes, such as sterilisation, could influence the protein digestibility.

Lysine deficiency is a major nutritional problem faced by poor people living in the arid and semi-arid tropics who depend on sorghum as their staple food. This is because of poor lysine content and digestibility of sorghum proteins, which aggravates when sorghum is cooked in food. To address this nutritional problem, compositing with locally available lysine-rich legumes has been proposed. Therefore, this study investigated the effects of compositing with the African grain legume, cowpea, on the protein and functional quality of important traditional African sorghum foods. Two sorghum cultivars, a red, tannin (NS 5511) and a white tan plant, non-tannin (Orbit) composited with cowpea at 70:30 ratio, were used to prepare three traditional sorghum foods, ugali (unfermented thick porridge), uji (fermented thin porridge) and injera (fermented flatbread). The protein quality of the traditional sorghum foods was determined by measuring their protein contents, lysine and reactive lysine contents, and in vitro protein digestibility. The functional properties of the foods were studied using instrumental texture analysis. Other sensory properties of ugali were determined using a trained sensory panel. Compositing with cowpea increased the protein contents of the foods by up to 35% and 57% for NS 5511 and Orbit foods, respectively. Lysine contents of the food proteins increased by 67% to 139%. Reactive lysine content increased by 10% to 75%. Protein digestibility of the foods increased by 13% to 62%. There was approximately three- and two-fold increase in protein digestibility corrected amino score (PDCAAS) of NS 5511 and Orbit foods, respectively, due to addition of cowpea. However, Orbit-plus-cowpea foods still had better protein quality than NS 5511-plus-cowpea foods, primarily because of the tannins in the latter which bind the proteins thereby lowering their digestibility. Compositing reduced paste peak viscosity (PV) and cool paste viscosity (CPV) of uji porridge by 6% to 23%, and 6% to 12%, respectively, probably as a result of decreasing porridge starch content. Principal component analysis (PCA) showed that compositing contributed 38% of the variation in 17 sensory attributes of ugali. Compositing imparted cowpea flavour to ugali. Most of the variation in sensory properties (59%) of ugali was due to the quality characteristics of the sorghum cultivars. Compositing increased the stiffness of NS 5511 injera by up to 25%, while it reduced the stiffness of Orbit injera by up to 12%. These differences in stiffness suggested a weakening effect of weaker H-bonding between tannins and other food polymers such as proteins instead of stronger covalent bonds like those involved in proteins-protein interactions. Compositing important traditional sorghum foods with cowpea has potential for helping to solve lysine deficiency faced by sorghum consumers in the semi-arid tropics. However, it introduces cowpea flavour which may need to be eliminated, in foods intended for consumers not accustomed to cowpea flavour. Copyright

A soja (Glycine max (L.) Merrill) é uma leguminosa de importante significado na alimentação humana em decorrência de suas propriedades nutricionais e funcionais. Com o melhoramento genético, surgem novos cultivares com sabor melhorado e com composição química modificada, conduzindo à necessidade de estudos para avaliar a concentração de nutrientes e de fatores antinutricionais. Neste estudo avaliou-se a composição centesimal, a concentração de minerais, de fitato, a atividade de urease e do inibidor de tripsina, a categorização nutricional por porção, o perfil aminoacídico, a solubilidade proteica, a biodisponibilidade de ferro e a qualidade proteica da farinha de soja, com e sem casca, do cultivar, UFVTN 105AP, tratadas a 150o C por 30 minutos. Para avaliar a biodisponibilidade de ferro utilizou-se o método dedepleção-repleção de hemoglobina em ratos machos Wistar. Os animais receberam dieta de depleção de ferro por 21 dias. Na fase de repleção, que durou 14 dias, o grupo controle (sulfato ferroso) e os dois grupos testes (farinha de soja com casca e sem casca) foram tratados com 6, 12 e 24 ppm de ferro. A qualidade proteica foi avaliada em ratos machos Wistar, distribuídos ao acaso em 4 grupos (n= 6), durante 14 dias. Os dois grupos testes receberam dietas àbase de farinhas de soja com e sem casca, um grupo recebeu dieta livre de nitrogênio e o grupo controle recebeu dieta à base de caseína. Avaliou-se o ganho de peso (GP), o consumo alimentar (CA), o coeficiente de eficiência alimentar (CEA), a razão da eficiência proteica (PER), a razão proteica líquida (NPR), a digestibilidade verdadeira (DV) e o escore químico corrigido pela digestibilidade (PDCAAS). A farinha de soja com casca apresentou maior teor de fibra alimentar total, cálcio e ferro e menor concentração de proteína e ácido fítico do que a soja sem casca. A razão molar fitato: ferro foi duas vezes menor que a farinha de soja sem casca e a razão molar fitato:zinco também foi menor. Para uma porção de 50 g do produto, as farinhas foram classificadas como excelente fonte de proteína, Cu, Mg, Zn e Mn, boa fonte de lipídio, fibra alimentar e K e fonte de Ca. Em relação ao Fe, a farinha com casca foi classificada como excelente fonte e a sem casca como boa fonte. O tratamento térmico reduziu a atividade de urease, inativou os inibidores de tripsina, e não superaqueceu as farinhas mantendo a solubilidade protéica superior a 85%. O perfil aminoacídico das farinhas de soja com e sem casca foram semelhantes entre si, sendo limitante para valina, apenas pelo padrão da FAO/WHO de recomendação nutricional. O ganho de hemoglobina (GH) no grupo da farinha de soja com casca foi similar ao do grupo controle (p<0,05). A farinha de soja sem casca apresentou GH inferior comparado ao grupo controle (p>0,05) na concentração de 24 ppm de ferro. O Valor Relativo de Biodisponibilidade (VRB) da farinha de soja com casca e sem casca foi 68,5% e 67,1%, respectivamente, em relação ao sulfato ferroso. No ensaio de qualidade proteica, o CEA e o NPR não diferiram (p>0,05) entre os grupos experimentais. O PER da farinha de soja sem casca foi semelhante (p>0,05) ao da caseína. Embora o PER da farinha de soja com casca tenha sido inferior (p<0,05) ao da caseína, este não diferiu (p>0,05) da farinha de soja sem casca. A DV das farinhas de soja com e sem casca não diferiram entre si (p>0,05), mas foi inferior à caseína (p<0,05), e o PDCCAS foi menor que a DV, em função do aminoácido limitante. Os índices de qualidade proteica, PER e NPR, indicaram que as farinhas foram adequadas para promover o crescimento e o desenvolvimento dos animais. A digestibilidade verdadeira foi elevada, embora tenha sido inferior à caseína. O melhoramento genético proporcionou equilíbrio qualitativamente e quantitativamente dos aminoácidos essenciais, com exceção da valina. A produção de farinha de soja com casca pode representar uma valiosa estratégia para aumentar a ingestão de fibra alimentar, e suprir 35% a mais de ferro do que a soja sem casca. O novo cultivar pode ser usado para auxiliar a suprir a necessidade de ferro de indivíduos com baixa ingestão em dietas convencionais e não convencionais. Além disso, o processamento da soja favoreceu o aproveitamento biológico das proteínas, indicando que o grão de soja deve ser utilizado de forma integral, para a produção de farinhas. | The soybean (Glycine max (L.) Merrill) is an important legume to human nutrition due to its nutritional and functional properties. It is important to establish and research a new cultivar of soybean to improve taste and chemical composition and decrease anti-nutritional factors. Therefore, the aim of this study was to evaluate the centesimal composition, mineral concentration, phytic acid, urease activity, tripsin inhibitor, nutritional categorization by serving size, amino acid profile, protein solubility, iron bioavailability and protein quality of a hull and hulless soybean flour from the UFVTN 105AP cultivar, heat-treated at 150o C for 30 minutes. Iron bioavailability was evaluated by the hemoglobin iron-depletion-repletion method in male Wistar rats. The animals were feed a depletion diet for 21 days and a repletion diet for 14 days. In the repletion phase, the control diet (ferrous sulphate) and the two test diets (hulled and hulless soy flour) were tested with 6, 12 and 24 ppm of iron. The protein quality was evaluated in male Wistar rats randomly to 4 groups (n= 6/group), for 14 days. Two groups (test) received their hulled and hulless soybean flour test meals, one group received a diet without protein and another received a casein diet. Weight gain (WG), feed intake (FI), food efficiency ratio (FER), protein efficiency ratio (PER), net protein ratio (NPR), true digestibility (TD) and protein digestibility&#8211;corrected amino acid score (PDCAAS) were determined. The hulled soy flour showed higher total alimentary fiber, calcium, iron, lower protein and phytic acid than the hulless soybean flour. The phytic acid:iron molar ration was two times lower that the hulless soy flour and the phytic acid: zinc molar ration was also lower. The serving size (50 g) of the flours was classified as an excellent source of protein, Cu, Mg, Zn and Mn, a good source of lipids, dietary fiber, and K and a source of Ca. For iron, the hulled soy flour was classified as an excellent source and the hulless soy flour as a good source. The heat-treatment decreased urease activity inhibited the tripsin inhibitor and increased protein solubility in both flours. The amino acid profile of hulled and hulless soy flour had been similar between themselves, being limiting only to valin by FAO/WHO nutritional requirements. A similarity of the hemoglobin serum gain between the control (ferrous sulphate) and test groups (hulled and hulless soybean flour) was observed. However, the group treated with hulless soy flour contained iron at a 24 ppm level showing inferior values compared to the control (p< 0.05). The relative iron bioavailability of the hulled soybean flour and hulless soybean flour was 68.5% and 67.1%, respectively, in relation to ferrous sulphate. In the protein quality assay, the PER and NPR did not differ (p> 0.05) among experimental groups. The PER of the hulless soy flour appeared similar to casein (p> 0.05). Although the PER of the hulled soy flour was inferior (p<0.05) to casein, it did not differ (p>0.05) from the hulless soy flour. The TD of hulled and hulless soy flour did not differed between themselves (p> 0.05), but were inferior to casein (p<0.05). The PDCCAS was lower than the TD, probably by limiting amino acids. The protein quality from PER and NPR indicated that the flours promoted adequate growth and development of the animals. True digestibility was high, but was inferior to casein. The genetic improvement provided an adequate balance of essential amino acids, qualitatively and quantitatively, with the exception of valin. The hulled flour can represent a valuable strategy to increase the dietary fiber intake, and to supply 35% more iron than the hulless soybean flour. A new cultivar can be used to assist iron requirements of individuals with low iron intake in conventional and non conventional diets. Moreover, the soybean processing improved the proteins quality, indicating the use of the hulled soybean flour. | Conselho Nacional de Desenvolvimento Científico e Tecnológico